JP2009252625A - Lead-acid battery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lead-acid battery capable of improving battery performance by reducing voltage drop due to an electrode pole in high output and high input, suppressing fusion of the electrode pole due to a battery short-circuit and rupture of the electrode pole even in a condition where strong vibration is applied, and reducing mass, and excelling in reliability. <P>SOLUTION: A tubular body formed of a material having lower electric resistance than that of an electrode pole base material and having excellent mechanical strength is made present in an electrode pole formed of a lead alloy, and led out from an electrode plate group constituting an end cell of this lead-acid battery comprising the electrode plate group composed of a positive electrode plate, a negative electrode plate and a separator. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a lead-acid battery.

  In recent years, there has been a demand for improvement in vehicle fuel efficiency from the viewpoint of the global environment, and the development of idling stop vehicles has been promoted, and lead-acid batteries corresponding thereto have been required. Lead-acid batteries in idling stop vehicles are frequently charged and discharged by large currents, such as large current discharges due to engine start and restart after stopping, and large current charges due to regenerative energy during vehicle braking. Will be repeated.

  For this reason, the lead storage battery is required to have high output and high input characteristics and light weight. One component that makes up a lead-acid battery that corresponds to this is the pole pole, and the conventional lead alloy product has a high electrical resistance when high output and high input are required, and the amount of lead used to reduce the electrical resistance Increasing the weight increases the weight, making it one of the parts to be improved. On the other hand, in recent lead-acid batteries, the electrode plate is lowered in order to reduce water replenishment and the electrolyte solution on the electrode plate group is held in a large amount, so that the level difference of the liquid level increases and the pole column tends to become longer.

  If the electrolyte level significantly decreases as the battery reaches the end of its life, the exposed part of the pole column in the cell chamber increases, and if an external short circuit occurs in such a state, the battery energy flows all at once and the pole column itself However, when it reaches the melting point of the lead alloy of the main material, it may blow out. On the other hand, the portion where the pole column is immersed in the electrolytic solution can be prevented from fusing because the generated heat can be suppressed by radiating heat into the electrolytic solution.

  In particular, when the battery is being charged or immediately after charging, the generated gas is filled inside, and there is a possibility that the spark may be caused to blow the storage battery due to the spark of the pole pole. Also, in environments where strong vibrations are applied to the battery, stress is directly applied to the long pole pole, and the pole poles mainly composed of lead alloys lack mechanical strength, and the pole poles themselves break due to prolonged strong vibration. Sometimes. Similarly, the battery may be ruptured by the spark at the time of the rupture.

  At present, the pole poles that are generally used are those in which the amount of lead alloy used is large and heavy in mass because the entire pole pole is made of lead alloy. In Cited Document 1, it has been proposed to insert a metal core made of copper or copper alloy into the pole and terminal portion of a storage battery that discharges a large current, and to reduce electric resistance. Although it is used for a large lead-acid battery that is used in a stationary manner, it has not been designed with the weight reduction in mind, so it cannot be said that the weight reduction is sufficient.

However, the poles of the lead-acid battery for start-up are a welding method for preparing the pole column parts before forming the shelf of the electrode plate group, and a caston strap that simultaneously forms the pole column when forming the electrode plate group shelf. Although there is a difference from the method, in any case, the pole column is manufactured by a casting method and is merely formed in a columnar shape made of a single lead alloy derived from the electrode plate group.
Japanese Patent Laid-Open No. 10-172535

  As described above, a lead-acid battery with excellent reliability that suppresses pole column breakage even in the state where polar column fusing and strong vibration are applied due to battery short-circuit while improving battery characteristics of charge / discharge by large current, and enables mass reduction Is to provide.

  In order to solve the above-mentioned problem, the invention according to claim 1 of the present invention is derived from the electrode plate group constituting the end cell in the lead storage battery having the electrode plate group constituted by the positive electrode plate, the negative electrode plate and the separator. The lead-acid battery is characterized in that a cylindrical body having a lower electric resistance than the pole column base material exists inside the pole column made of the lead alloy.

  The invention according to claim 2 of the present invention shows the lead-acid battery according to claim 1, wherein the cylindrical body uses a metal having a melting point higher than that of the pole column base material.

  The invention according to claim 3 of the present invention is the lead storage battery according to claim 1, wherein the cylindrical body is made of a metal having higher mechanical strength than the pole base material. is there.

  The invention according to claim 4 of the present invention shows the lead storage battery according to claims 2 and 3, wherein the surface of the cylindrical body is subjected to lead plating.

  The invention according to claim 5 of the present invention is the lead storage battery according to any one of claims 1 to 4, wherein the entire surface of the cylindrical body is covered with a pole column base material.

  According to the configuration of the present invention described above, the high output and high input characteristics are improved by the presence of a substance having an electric resistance lower than that of the pole column base material inside the pole column, and the presence of a metal having a high melting point. Lead alloy that can prevent the battery from rupturing due to sparks generated at the time of fusing or rupturing, and can prevent rupture due to the presence of high-strength metal and fusing of the pole even when a large current flows Since the amount can be reduced, the remarkable effect that the weight can be reduced can be obtained.

  A configuration of the lead storage battery according to the embodiment of the present invention will be described.

  FIG. 1 is a perspective view showing a partial cross section of the lead storage battery of the present invention. In the battery case 1, an electrode plate group 2 composed of a positive electrode plate, a negative electrode plate, and a separator is inserted into each cell, and the electrode plate group 2 of the end cell 3 existing at both ends of the monoblock battery case in which the cells are arranged in a row. Are provided with a pole column 5 for leading electricity to the outside from a shelf 4 to which a plurality of electrode plates are connected, and a connection body 6 for electrical connection with an adjacent cell via a partition wall. Further, when the battery case 1 and the lid 7 are integrally welded, the pole column 5 is inserted into a cylindrical portion 8a existing at the center of the external terminal 8 provided integrally with the lid, and is externally attached after the battery case and the lid are welded. The upper ends of the terminals 8 are connected by welding.

  FIG. 2 is a diagram showing a cross section of a pole column and a terminal of the lead storage battery of the present invention. A copper cylindrical body 9 that opens up and down is embedded in the inside of the pole 5, and the surface of the cylindrical body is completely covered with a lead alloy 9 a that is a base material of the pole pole, and is a copper cylinder. A space portion 9b that opens downward exists inside the pole 5 in which the body 9 is embedded. The tip of the pole 5 is welded to a lead alloy terminal bushing provided integrally with the lid 7 to form an external terminal 8.

  The external terminal 8 present in the lid 7 made of a synthetic resin mainly composed of polypropylene constituting the battery exterior has a lead alloy terminal bushing made of a lead-antimony alloy having a taper shape placed in the mold when the lid is molded. Create by integral molding by insert molding.

  For the cylindrical body 9, it is necessary to select a material having lower electrical resistance, higher melting point and higher mechanical strength than a lead alloy covering the outside of the pole column 5, and copper, aluminum, and steel can be applied. However, it is preferable to use copper from the viewpoint of emphasizing electrical resistance.

  As an example of the pole 5, when the outer diameter is 90 mm in height and the diameter is 10 mm, a copper tubular body is prepared with an outer diameter of 6 mm, an inner diameter of 4 mm, and a cylinder with a thickness of 1 mm. Can be changed according to the shape of the battery. Furthermore, the height (length) of the cylindrical body 9 is set to 85 mm, which is slightly shorter than the height of the pole column 5, and the cylindrical body has good adhesion when the surface of the cylindrical body is covered with a lead alloy in a later process. Therefore, solder plating of 60% by mass of lead and 40% by mass of tin is performed.

  FIG. 3 is an explanatory cross-sectional view of covering the lead alloy on the surface of the cylindrical body. A cylindrical body 9 made of copper is disposed in the central space portion 10a of the casting mold 10 and a molten lead-antimony alloy 11 is poured from the upper portion of the casting mold 10 to be cooled and solidified. Get.

  FIG. 4 is a cross-sectional view of the polar column precursor, and this polar column precursor 5a is used at a position where the vertical direction is inverted when actually used for the electrode plate group. The surface of the cylindrical body 9 is covered with a lead alloy 9a to form an outer shape as the pole column 5, and a portion corresponding to the center of the pole column 5 has a cylindrical space portion 9b opened up and down, The tip of the cylindrical body (portion connected to the electrode plate group) located at the upper part of the casting mold 10 is covered with a lead alloy and has a flat portion 12 integrally. The exposed portion 5b of copper exists in the polar column precursor at the contact portion of the cylindrical body that was in contact with the electrode.

  In the electrode plate group 2 of the end cell 3, the pole column precursor 5 a is inverted, the exposed portion 5 b of copper is positioned in the upper part, the flat part 12 existing in the lower part is connected to the shelf part 4, and one counter electrode The shelf 4 is connected to the adjacent cell via the connection body 6. Similarly, the electrode plate group of the other intermediate cell is housed in each cell and connected to an adjacent cell via a partition wall, and then the tip of the electrode column precursor 5a existing in the electrode plate group 2 of the end cell is attached to the lid 7. The exposed portion 5b of the pole column precursor copper is covered with the lead alloy of the external terminal by being inserted into the cylindrical portion 8a existing at the center of the integrated external terminal 8 and burning the upper portion of the external terminal.

  Thereafter, the lead storage battery of the present invention is prepared by a conventional method in which dilute sulfuric acid serving as an electrolytic solution is injected and formed.

  In the cross section of the pole column and the terminal part of the lead storage battery of the present invention, a copper cylindrical body having a constant pole column diameter of 10 mm is used, the distance between the pole column surface and the cylindrical body, the cylindrical body thickness, the cylindrical shape A 12V36Ah starting lead-acid battery according to an example of the present invention and a comparative example was prepared by changing the inner surface of the body and the inner surface of the pole column, and the inner surface of the pole column and the center interval of the pole column.

  In the comparative example, a lead alloy having the same size and shape was used as a conventional pole column. These structural conditions are shown in Table 1.

For each test battery shown in Table 1, the following four items were evaluated.
(1) Mass of pole pole parts before battery assembly (2 pieces)
(2) Voltage drop in the 5th second when discharging at 300 A current at an ambient temperature of 25 ° C. (3) The vibration direction is front and back, the acceleration is 49.0 m / S ² , and the vibration time is 2 hours. Confirmation of disconnection of pole pole by battery disassembly during vibration test (4) Electrode by battery disassembly after conducting short circuit test by circuit created using wire and knife switch with outer diameter of about 4.2mm ² Table 2 shows the results of tests conducted on the test batteries shown in Table 1 above.

  From the results shown in Table 2, the following effects are obtained according to the configuration of the present invention.

  The mass of the pole column was able to be reduced to about 76 to 98% in the battery of the configuration of the present invention with respect to the battery A of the comparative example.

  The voltage drop was reduced to about 13% in the battery H of the configuration of the present invention with respect to the battery A of the comparative example, and the highest effect was obtained. It was confirmed that the battery C, which has little effect, was reduced to 42%, and a significant improvement in voltage drop was confirmed.

  Here, from the two viewpoints of mass and voltage drop, when the battery D and the battery F are compared, the magnitude of the voltage drop is the same, but the battery F can further reduce the mass, and has the same cylindrical shape. When the body was used, it was possible to achieve the same reduction in voltage drop and a reduction in mass by having a space inside.

  In the vibration test, the disconnection of the pole column was confirmed in the battery A and the battery B of the conventional configuration of the comparative example from the observation result by the battery disassembly after the test was completed. However, no disconnection of the pole was confirmed. Therefore, it can be seen that the battery of the configuration of the present invention has increased mechanical strength of the pole column portion.

  Similarly, in the short circuit test, the battery A of the comparative example was melted immediately below the external connection terminal portion exposed from the electrolytic solution, based on the observation result by the battery disassembly after the test was completed. In each of the batteries C to H, no disconnection of the pole column was confirmed. The fusing just below the external connection terminals was because the distance from the electrolytic solution surface was far away and the generated heat could not be released to the electrolytic solution.

  This is because, in the battery A and the battery B of the conventional configuration, when hydrogen gas and oxygen gas are present, such as during charging of the battery, the spark ignites the gas and the battery bursts. Regarding the batteries C to I having the configuration, it means that even if gas stays inside the battery, no rupture due to fusing of the pole column occurs.

  In this embodiment, the cylindrical body inside the pole pole is made of copper and embedded, but it has a lower electrical resistance than lead alloy depending on the purpose, such as aluminum and steel for cost reduction in order to reduce weight. A similar effect can be obtained by using a pole column that covers the entire surface of the cylindrical body using the lead alloy.

  According to the present invention, mass reduction, suppression of voltage drop during charging / discharging with a large current, vibration resistance, and remarkable effects of not causing pole column fusing of an exposed portion from an electrolyte even when an external short circuit occurs Is obtained.

  By improving the pole column as described above, the present invention can improve the battery characteristics due to a large current, suppress the pole column fusing and rupture due to the battery short circuit and large vibration, and has high reliability that enables mass reduction. Lead-acid battery is obtained, and its industrial value is high.

The perspective view which shows the partial cross section of the lead acid battery of this invention The figure which shows the cross section of the pole column and terminal of the lead acid battery of this invention Sectional drawing for description which covers a lead alloy on the surface of the cylindrical body of the present invention Sectional view of the polar column precursor of the present invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Battery case 2 Electrode plate group 3 End cell 4 Shelf part 5 Polar pillar 5a Polar pillar precursor 5b Exposed part 6 Connection body 7 Lid 8 External terminal 8a Cylindrical part 9 Cylindrical body 9a Lead alloy 9b Space part 10 Casting mold 10a Center Space part 11 Pouring 12 Flat part

Claims (5)

In a lead storage battery having an electrode plate group composed of a positive electrode plate, a negative electrode plate, and a separator, the inside of the pole column made of a lead alloy derived from the electrode plate group constituting the end cell is more electrically than the electrode column base material. A lead-acid battery characterized by the presence of a low resistance cylindrical body. The lead-acid battery according to claim 1, wherein the cylindrical body uses a metal having a melting point higher than that of the pole column base material. The lead acid battery according to claim 1, wherein the cylindrical body is made of a metal having higher mechanical strength than the pole column base material. 4. The lead acid battery according to claim 2, wherein the surface of the cylindrical body is subjected to lead plating. The lead acid battery according to claim 1, wherein the entire surface of the cylindrical body is covered with a pole column base material.

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